Would also be easier for someone like her, a presumably untrained fighter.
The fact that Dimitri was just going to let her though, shows that his snap back into reality wasn't instant, it'd been a process. She would have done this when Byleth first found him he wouldn't just sit there calmly, he'd fight back, not caring that this was a small, sweet looking woman. All he'd have to know is that she's from the Empire and she'd be dead. But by the time she actually did, he was pretty much like "Well shit, it's been lovely...NOT. I'm ready to join the ghosts who haunt me." I noticed the gradual transition and it was cool to watch.
This is some decent writing, at least.